Section 6: Storm Water Management

Introduction

Maintenance of the highway system should be performed not
only with the goals of safety and efficiency but also in an environmentally
sensitive manner. One of the most important environmental issues
confronting the department is water quality. Although the impacts
of runoff pollution on receiving waters from our facilities may
not be significant, it is generally recognized that responsible
agencies may be required by federal and state regulations to apply
the best management practices available to reduce pollutant loads
entering water bodies.

Policy

The department should use best management practices when contracting
for or performing maintenance on the state's highways and rights-of-way.
Although the publication "Storm Water Management Guidelines for
Construction Activities" was developed for construction, it is a
good guide and has measures that can be used directly for maintenance
activities. One of the basic principles is to ensure proper use,
storage and disposal of materials to minimize and/or prevent storm water
pollution. The development and implementation of best management
practices minimize runoff of contaminants from pavements and bridges.

This permit was issued as part of the Texas Pollution Discharge
Elimination System (TPDES), for discharging storm water from construction
sites to the surface waters of the state. Although the title of
the permit only mentions construction, it also affects maintenance.
It allows storm water discharges from state force contract maintenance
work sites provided that specific guidelines are followed. Work
that disturbs less than one acre is generally excluded from the
regulatory requirements. Therefore, unless a work activity is excluded
from construction general permit (CGP), it must comply with the
CGP's requirements.

CGP Excluded Activities

Work "performed to maintain the
original line and grade, hydraulic capacity, and original purpose
of a ditch, channel, or other similar storm water conveyance." In
other words, ditch and channel cleaning for maintenance reasons.

While these activities are excluded from the CGP requirements,
they may still require a U.S. Army Corps of Engineers 404 permit.
In addition, even if an activity is excluded, but it has the potential to
produce erosion, always employ best management practices.

Projects not exempted by the CGP that
disturb one or more acres require a Storm Water Pollution Prevention
Plan (SW3P) and a Construction Site Notice (CSN) to be posted on
the site prior to beginning work.

Projects not exempted by the CGP that
disturb five or more acres require a Notice of Intent (NOI) to be
submitted to TCEQ prior to the commencement of earth disturbing
activities. A Notice of Termination (NOT) must be submitted to TCEQ
after construction is complete and the site has been re-vegetated
to 70 percent of the native background cover.